// pot odds · bet size

3× pot overbet: pot odds, equity needed and MDF

What a bet of three times the pot asks of the caller and of the bettor, worked out exactly, with the formula and the numbers in it.

a call needs42.9%exactly 3 / 7
pot odds1.33 to 14 : 3
MDF25.0%defend 1 / 4
a bluff must work75.0%3 / 4 of the time

A bet of three times the pot is the near-shove that turns up when stacks are deep and the pot is small. Here is everything it asks, worked in units of the pot (P = 1, B = 3) and then in a 12 bb pot, where the bet is 36 bb.

pot odds        (P + B) : B   = 4 : 3 = 1.33 to 1
call needs      B / (P + 2B)  = 3 / 7 = 42.86%
MDF             P / (P + B)   = 1 / 4 = 25.00%
bluff must work B / (P + B)   = 3 / 4 = 75.00%

in a 12 bb pot: call 36 bb to win 48 bb; final pot 84 bb
break-even equity = 36 bb / 84 bb = 42.86%

Can a draw call it?

Facing three times the pot on the turn, with one card to come, a draw needs at least 20 clean outs to call on the price alone (20 / 46 = 43.5% against 42.9% needed). On the flop, if the call only buys the turn, it needs 21; all-in on the flop, seeing both cards, it needs 12. A flush draw on the turn hits 19.6% of the time, so it is short, and must win about 8.33 pot more on the river when it hits (100 bb in a 12 bb pot).

Which draws can call a 3× pot overbet
DrawFacing a flop betFacing a turn betAll-in on the flop
Gutshot (4)8.5% needs +28.25 pot8.7% needs +27.50 pot16.5% folds
Open-ended straight draw (8)17.0% needs +10.63 pot17.4% needs +10.25 pot31.5% folds
Flush draw (9)19.1% needs +8.67 pot19.6% needs +8.33 pot35.0% folds
Flush draw + gutshot (12)25.5% needs +4.75 pot26.1% needs +4.50 pot45.0% calls
Flush draw + open-ender (15)31.9% needs +2.40 pot32.6% needs +2.20 pot54.1% calls

Green calls on the direct price. Red shows the implied odds still missing: the extra the draw must win when it hits, as a multiple of the pot before the bet. All-in there is nothing left to win, so a short draw folds.

Defending against it

A pure bluff of three times the pot risks 3 to win 1, so it profits if you fold more than 75.0% of the time. To stop any two cards from betting at a profit you have to continue with 25.0% of the range you arrived with: the minimum defence frequency. Defend ten points less, 15.0%, and every zero-equity bluff earns +0.40 pot on average:

bluff EV = fold × P − call × B
         = 0.850 × 1 − 0.150 × 3.000 = +0.40 pot

Betting it on the river

With a polarised range, nuts or air, the bettor makes a bluff-catcher indifferent by bluffing 3 / 7 of their bets, 42.9%. That is 4 : 3 value to bluffs, or about 7.5 bluff combos for every 10 value combos. The bluff share is the caller’s required equity again, which is the indifference: with P = 1 and B = 3, a bluff-catcher that calls wins 3 / 7 × 4 and loses 4 / 7 × 3, which are both 12 / 7 of a pot unit. See the bluff-to-value ratio for what happens either side of it.

Next to the other sizes

One size down, a 2× pot overbet asks for 40.0%. Bigger bets ask more of the caller, but never more than half: as B grows, B / (P + 2B) creeps towards 50% and never reaches it.

Pot odds, required equity and MDF by bet size
BetPot oddsCall needsMDFBluff must workRiver value : bluffOuts to call a turn bet
Quarter-pot bet5 to 116.7%80.0%20.0%5 : 18
Third-pot bet4 to 120.0%75.0%25.0%4 : 110
Half-pot bet3 to 125.0%66.7%33.3%3 : 112
Two-thirds-pot bet2.5 to 128.6%60.0%40.0%5 : 214
Three-quarter-pot bet2.33 to 130.0%57.1%42.9%7 : 314
Pot-sized bet2 to 133.3%50.0%50.0%2 : 116
1.5× pot overbet1.67 to 137.5%40.0%60.0%5 : 318
2× pot overbet1.5 to 140.0%33.3%66.7%3 : 219
3× pot overbet1.33 to 142.9%25.0%75.0%4 : 320

Every bet size

The ideas behind the numbers

// what is computed and what is assumed
  • The prices are exact. Pot odds, required equity, MDF and the bluff frequencies are arithmetic on the pot and the bet, printed as reduced fractions. Nothing is rounded until it is displayed.
  • Draw odds are counted. The chance of hitting comes from the outs chart, which deals every turn and river. We assume clean outs: every out wins and nothing else does. Real draws are dirtier, and against a stated range the spot check counts the real equity instead.
  • No rake, no future betting unless a page says otherwise. Implied odds are the one place we price a later street, and that page states its model.
  • MDF and the river ratio are a toy game, not a solver output: a bettor with only the nuts or air, a caller with only bluff-catchers. They say what stops the other player profiting automatically. They are not a strategy for any single hand.